While I have the radio out and am trying to replace warning light bulbs and the heater control illumination light bulb, I noticed a bright green wire with a gray bullet connector socket hanging down. See attached picture. Does anyone know the factory's intent for this wire? The view is through the radio opening in the center panel.

Jim, I just did the radio on 18309 and it had the same thing. 'Bout drove me nuts. My car had air install previously. Othewise I'm wondering with you.. Hope someone has the answer. I've reinstalled the radio etal and so far all is working.....

Judson, you must have a different wiring diagram than mine. Cable number 85 on mine is GW-85-SC. It connects between #2 in the Steering Column 9 Way Socket and the RH Flasher Junction. I don't see a G-85-SC. My wiring diagram is glued into the rear cover of the "Jensen - Healey Owners Handbook" that was in the trunk of 14482 when I bought it used in 1982. The Mystery Wire photo I took featured 19336 which came without an owners manual. Were there more than one JH wiring diagrams? If so, it helps explain why I'm having trouble making sense of some of the circuits, such as those connected to the Lucas alternator.

My (1974?) copy of the parts list shows three different wiring harnesses:
90586, used on LHD cars to VIN 13349
91408, used on RHD cars apparently regardless of VIN
92991, used on LHD cars VIN 13350 up.

In addition, the GTs reportedly use a different wiring harness. I suppose that some very late cars may have had the GT harness, or some experimental predecessor thereof, installed during manufacture. But the Jensen factory was generally pretty good about changing part numbers when parts were revised, so one can reasonably expect all other JHs to have one of the harnesses listed above.

In addition to the Delta Motorsports wiring diagram, there are several others of which I'm aware. The Jensen Motors online version dated 1999, seems oriented towards European cars and lacks the special wiring used in North American vehicles. I don't have copies of the others, but IIRC they were all subtly different from each other, and at least one was both incomplete and wrong. For what it's worth, my car is a MkII with a 92991 harness, and before I removed the seat belt warning system wiring, there was a 100% correspondence between its wiring and Delta's diagram.

On the Delta Motorsports wiring diagram:

(1) There is a wire G-85-SC that runs from the IGN FUSE JUNC R.H. to a bullet receptacle labelled O/D FEED. This wire is powered when the ignition switch is in the RUN position. I would presume this to be the mystery wire in question.

(2) There is a wire WU-84-SC that runs from the IGN SW 5-WAY SOCKET to a bullet receptacle labelled RADIO. This wire is powered when the ignition switch is in the ACCESSORY or RUN positions.

Thanks again Mark. My next order from Delta will include their wiring diagram. Too bad it's not immediately accessable on- line somewhere. I have downloaded and printed the 1999 Jensen Motors diagram but it's less useful since it shows only cable colors and not the full wiring codes including cable numbers.